Private Sub CommandButton1_Click()
Dim msg$, oCell As Range
For Each oCell In Selection.Cells 'ou autre plage à définir tant que de besoin...
If oCell.Interior.ColorIndex = 3 Then msg = msg & ", " & oCell.Address(0, 0)
Next
MsgBox Right$(msg, Len(msg) + (Len(msg) > 0))
End Sub